/*!
 * Ext JS Library 3.3.0
 * Copyright(c) 2006-2010 Ext JS, Inc.
 * licensing@extjs.com
 * http://www.extjs.com/license
 */
Ext.namespace('Ext.ux.grid.filter');

/** 
 * @class Ext.ux.grid.filter.Filter
 * @extends Ext.util.Observable
 * Abstract base class for filter implementations.
 */
Ext.ux.grid.filter.Filter = Ext.extend(Ext.util.Observable, {
	/**
	 * @cfg {Boolean} active
	 * Indicates the initial status of the filter (defaults to false).
	 */
	active : false,
	/**
	 * True if this filter is active.  Use setActive() to alter after configuration.
	 * @type Boolean
	 * @property active
	 */
	/**
	 * @cfg {String} dataIndex
	 * The {@link Ext.data.Store} dataIndex of the field this filter represents.
	 * The dataIndex does not actually have to exist in the store.
	 */
	dataIndex : null,
	/**
	 * The filter configuration menu that will be installed into the filter submenu of a column menu.
	 * @type Ext.menu.Menu
	 * @property
	 */
	menu : null,
	/**
	 * @cfg {Number} updateBuffer
	 * Number of milliseconds to wait after user interaction to fire an update. Only supported
	 * by filters: 'list', 'numeric', and 'string'. Defaults to 500.
	 */
	updateBuffer : 500,

	constructor : function (config) {
		Ext.apply(this, config);

		this.addEvents(
			/**
			 * @event activate
			 * Fires when an inactive filter becomes active
			 * @param {Ext.ux.grid.filter.Filter} this
			 */
			'activate',
			/**
			 * @event deactivate
			 * Fires when an active filter becomes inactive
			 * @param {Ext.ux.grid.filter.Filter} this
			 */
			'deactivate',
			/**
			 * @event serialize
			 * Fires after the serialization process. Use this to attach additional parameters to serialization
			 * data before it is encoded and sent to the server.
			 * @param {Array/Object} data A map or collection of maps representing the current filter configuration.
			 * @param {Ext.ux.grid.filter.Filter} filter The filter being serialized.
			 */
			'serialize',
			/**
			 * @event update
			 * Fires when a filter configuration has changed
			 * @param {Ext.ux.grid.filter.Filter} this The filter object.
			 */
			'update'
		);
		Ext.ux.grid.filter.Filter.superclass.constructor.call(this);

		this.menu = new Ext.menu.Menu();
		this.init(config);
		if(config && config.value){
			this.setValue(config.value);
			this.setActive(config.active !== false, true);
			delete config.value;
		}
	},

	/**
	 * Destroys this filter by purging any event listeners, and removing any menus.
	 */
	destroy : function(){
		if (this.menu){
			this.menu.destroy();
		}
		this.purgeListeners();
	},

	/**
	 * Template method to be implemented by all subclasses that is to
	 * initialize the filter and install required menu items.
	 * Defaults to Ext.emptyFn.
	 */
	init : Ext.emptyFn,

	/**
	 * Template method to be implemented by all subclasses that is to
	 * get and return the value of the filter.
	 * Defaults to Ext.emptyFn.
	 * @return {Object} The 'serialized' form of this filter
	 * @methodOf Ext.ux.grid.filter.Filter
	 */
	getValue : Ext.emptyFn,

	/**
	 * Template method to be implemented by all subclasses that is to
	 * set the value of the filter and fire the 'update' event.
	 * Defaults to Ext.emptyFn.
	 * @param {Object} data The value to set the filter
	 * @methodOf Ext.ux.grid.filter.Filter
	 */
	setValue : Ext.emptyFn,

	/**
	 * Template method to be implemented by all subclasses that is to
	 * return <tt>true</tt> if the filter has enough configuration information to be activated.
	 * Defaults to <tt>return true</tt>.
	 * @return {Boolean}
	 */
	isActivatable : function(){
		return true;
	},

	/**
	 * Template method to be implemented by all subclasses that is to
	 * get and return serialized filter data for transmission to the server.
	 * Defaults to Ext.emptyFn.
	 */
	getSerialArgs : Ext.emptyFn,

	/**
	 * Template method to be implemented by all subclasses that is to
	 * validates the provided Ext.data.Record against the filters configuration.
	 * Defaults to <tt>return true</tt>.
	 * @param {Ext.data.Record} record The record to validate
	 * @return {Boolean} true if the record is valid within the bounds
	 * of the filter, false otherwise.
	 */
	validateRecord : function(){
		return true;
	},

	/**
	 * Returns the serialized filter data for transmission to the server
	 * and fires the 'serialize' event.
	 * @return {Object/Array} An object or collection of objects containing
	 * key value pairs representing the current configuration of the filter.
	 * @methodOf Ext.ux.grid.filter.Filter
	 */
	serialize : function(){
		var args = this.getSerialArgs();
		this.fireEvent('serialize', args, this);
		return args;
	},

	/** @private */
	fireUpdate : function(){
		if (this.active) {
			this.fireEvent('update', this);
		}
		this.setActive(this.isActivatable());
	},

	/**
	 * Sets the status of the filter and fires the appropriate events.
	 * @param {Boolean} active        The new filter state.
	 * @param {Boolean} suppressEvent True to prevent events from being fired.
	 * @methodOf Ext.ux.grid.filter.Filter
	 */
	setActive : function(active, suppressEvent){
		if(this.active != active){
			this.active = active;
			if (suppressEvent !== true) {
				this.fireEvent(active ? 'activate' : 'deactivate', this);
			}
		}
	}
});